scholarly journals Kinetics of multi-step processes of thermal degradation of Co(II) complex with N-benzyloxycarbonylglycinato ligand. Deconvolution of DTG curves

2014 ◽  
Vol 46 (1) ◽  
pp. 37-53 ◽  
Author(s):  
M. Sumar-Ristovic ◽  
D.M. Minic ◽  
V. Blagojevic ◽  
K. Andjelkovic
Keyword(s):  
Thermal Decomposition ◽  
Activation Parameters ◽  
Elementary Step ◽  
Elementary Steps ◽  
Master Plot ◽  
Thermodynamic Activation Parameters ◽  
Ikp Method ◽  
Kinetic Triplet ◽  
Reaction Models ◽  
Kinetics Of

Thermal decomposition of Co(II) complex with N-benzyloxycarbonylglycinato ligand, [Co(N-Boc-gly)2(H2O)4]?2H2O, in non-isothermal conditions occurs in three complex steps. In order to investigate detail kinetics of first two steps, dehydration and ligand degradation, DTG curves were deconvoluted using product of Gaussian and Lorentzian function. It was shown that process of complex dehydration consists of three, while process of ligand fragmentation consist of five elementary steps. For elementary steps the kinetic triplet (Ea, Z and f(?)) was determinated. Kinetic parameters were obtained by application of IKP method. On the basis of M?lek?s criteria and Sest?k-Berggren's method, Sest?k-Berggren's model, f(?)=?M(1-?)N was suggested for all elementary steps, while Master plot method and Perez- Maqueda criteria confirmed suggested reaction models. The thermodynamic activation parameters were calculated for process of complex dehydration, and lifetime for first elementary step of the dehydration and ligand degradation processes was estimated.

Thermal decomposition kinetics of strontium oxalate

2007 ◽  
Vol 61 (5) ◽  
Author(s):  
F. Al-Newaiser ◽  
S. Al-Thabaiti ◽  
A. Al-Youbi ◽  
A. Obaid ◽  
M. Gabal
Keyword(s):  
Thermal Decomposition ◽  
Hexagonal Phase ◽  
Three Dimensional ◽  
Activation Parameters ◽  
Strontium Carbonate ◽  
Isothermal Tg ◽  
Diffusion Controlled ◽  
Reaction Models ◽  
Decomposition Behavior ◽  
Kinetics Of

AbstractThe thermal decomposition behavior in air of SrC2O4 · 1.25H2O was studied up to the formation of SrO using DTA-TG-DTG techniques. The decomposition proceeds through four well-defined steps. The first two steps are attributed to the dehydration of the salt, while the third and fourth ones are assigned to the decomposition of the anhydrous strontium oxalate into SrCO3 and the decomposition of SrCO3 to SrO, respectively. The exothermic DTA peak found at around 300°C is ascribed to the recrystallization of the anhydrous strontium oxalate. On the other hand, the endothermic DTA peak observed at 910°C can be attributed to the transition of orthorhombic-hexagonal phase of SrCO3. The kinetics of the thermal decomposition of anhydrous strontium oxalate and strontium carbonate, which are formed as stable intermediates, have been studied using non-isothermal TG technique. Analysis of kinetic data was carried out assuming various solid-state reaction models and applying three different computational methods. The data analysis according to the composite method showed that the anhydrous oxalate decomposition is best described by the two-dimensional diffusion-controlled mechanism (D2), while the decomposition of strontium carbonate is best fitted by means of the three-dimensional phase boundary-controlled mechanism (R3). The values of activation parameters obtained using different methods were compared and discussed.

Kinetic Study of the Oxidation of Alcohols with Quaternary Ammonium Permanganates

1993 ◽  
Vol 58 (8) ◽  
pp. 1777-1781 ◽  
Author(s):  
Robert Šumichrast ◽  
Vladislav Holba
Keyword(s):  
Kinetic Study ◽  
Catalytic Reaction ◽  
Rate Constants ◽  
Quaternary Ammonium ◽  
Iterative Procedure ◽  
Activation Parameters ◽  
Reaction Products ◽  
Thermodynamic Activation Parameters ◽  
Oxidation Of Alcohols ◽  
Kinetics Of

Kinetics of the oxidation of 2-propanol, 1-butanol, and 1-pentanol with tetraalkylammonium permanganates have been investigated as function of temperature. The studied reactions are partly autocatalytic, colloidal manganese dioxide as one of the reaction products has been identified as the autocatalyst.A computerized iterative procedure has been used in order to obtained the rate constants of both non-catalytic and catalytic reaction steps together with the thermodynamic activation parameters.

scholarly journals Kinetics and Mechanism of Oxidation of Diethanolamine and Triethanolamine by Potassium Ferrate

2011 ◽  
Vol 8 (2) ◽  
pp. 903-909 ◽  
Author(s):  
Shan Jinhuan ◽  
Zhang Jiying
Keyword(s):  
Activation Parameters ◽  
Rate Equations ◽  
Potassium Ferrate ◽  
Kinetics Of Oxidation ◽  
First Order ◽  
Order Dependence ◽  
Rate Determining Step ◽  
Thermodynamic Activation Parameters ◽  
Plausible Mechanism ◽  
Kinetics Of

The kinetics of oxidation of diethanolamine and triethanolamine by potassium ferrate(VI)in alkaline liquids at a constant ionic strength has been studied spectrophotometrically in the temperature range of 278.2K-293.2K. The reaction shows first order dependence on potassium ferrate(VI), first order dependence on each reductant, The observed rate constant (kobs) decreases with the increase in [OH-], the reaction is negative fraction order with respect to [OH-]. A plausible mechanism is proposed and the rate equations derived from the mechanism can explain all the experimental results. The rate constants of the rate-determining step and the thermodynamic activation parameters are calculated.

Kinetics of oxidation of cis-bis(ethylenediamine)isothiocyanatonitrocobalt(III) ion with peroxodisulphate

1979 ◽  
Vol 44 (12) ◽  
pp. 3588-3594 ◽  
Author(s):  
Vladislav Holba ◽  
Olga Volárová
Keyword(s):  
Ionic Strength ◽  
Rate Constants ◽  
Oxidation Kinetics ◽  
Reaction Rate ◽  
Salt Effect ◽  
Activation Parameters ◽  
Reaction Products ◽  
Kinetics Of Oxidation ◽  
Thermodynamic Activation Parameters ◽  
Kinetics Of

The oxidation kinetics of cis-bis(ethylenediamine)isothiocyanonitrocobalt(III) ion with peroxodisulphate was investigated in the medium of 0.01 M-HClO4 in dependence on the ionic strength and temperature and the reaction products were identified. Extrapolated values of thermodynamic activation parameters were determined from the temperature dependence of the rate constants extrapolated to zero ionic strength. The distance of the closest approach was estimated for the reacting ions by evaluating the primary salt effect. To elucidate the mechanism, the influence of the cyclic polyether 18-crown-6 on the reaction rate was followed.

scholarly journals Kinetics and Mechanism of Thermal Decomposition of 1-R-Substituted bis(1,1-Dinitromethyl-3-Nitro- 1,2,4-Triazole-5-yl)

2020 ◽  
pp. 25-30
Author(s):  
Lyudmila А. Kruglyakova ◽  
Rudolf S. Stepanov ◽  
Konstantin V. Pekhotin ◽  
Oksana А. Golubtsova
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Activation Parameters ◽  
Decomposition Kinetics ◽  
Mechanism Of Thermal Decomposition ◽  
Limiting Stage ◽  
Manometric Method ◽  
Steric Constant ◽  
Kinetics Of ◽  
Constant Activation Energy

Thermal decomposition kinetics of 1-substituted bis(1,1-dinitromethyl-3-Nitro-1,2,4-triazole- 5-yl) in solution of 1,3-dinitrobenzene is studied with manometric method under isothermal conditions. The limiting stage of thermal decomposition is homolytic break of C-NO2 bond in gem-dinitromethyl group; activation parameters of this stage are calculated. The reactivity of investigated compounds is analyzed. Correlation dependences between logarithm of rate constant, activation energy and steric constant of substituent R are obtained

Oxidation kinetics of trans-aqua-bis(ethylenediamine)-isothiocyanatocobalt(III) ion with peroxodisulphate

1979 ◽  
Vol 44 (4) ◽  
pp. 1052-1059 ◽  
Author(s):  
Olga Volárová ◽  
Vladislav Holba
Keyword(s):  
Ionic Strength ◽  
Temperature Dependence ◽  
Rate Constants ◽  
Oxidation Kinetics ◽  
Salt Effect ◽  
Activation Parameters ◽  
Thermodynamic Activation Parameters ◽  
Ionic Reactions ◽  
Kinetics Of

Oxidation kinetics of trans-aqua-bis(ethylenediamine)cobalt(III) ion with peroxodisulphate have been investigated in 0.01M-HClO4 medium within the ionic strength and temperature intervals 0.0411 to 0.4415M and 315.5 to 336.9 K, respectively. From the temperature dependence of the rate constants extrapolated to zero ionic strength the extrapolated values of thermodynamic activation parameters have been calculated. The data obtained by investigation of the primary salt effect have been confronted with relations valid for ionic reactions.

scholarly journals Kinetics and Mechanism of Oxidation of Isobutylamine and 1,4-Butanediamine by Potassium Ferrate

2011 ◽  
Vol 8 (3) ◽  
pp. 1371-1377
Author(s):  
Shan Jinhuan ◽  
Yang Yafeng
Keyword(s):  
Activation Parameters ◽  
Rate Equations ◽  
Potassium Ferrate ◽  
Kinetics Of Oxidation ◽  
First Order ◽  
Rate Determining Step ◽  
Thermodynamic Activation Parameters ◽  
Plausible Mechanism ◽  
Mechanism Of Oxidation ◽  
Kinetics Of

The kinetics of oxidation of isobutylamine and 1,4-butanediamine by home-made potassium ferrate(VI) at different conditions has been studied spectrophotometrically in the temperature range of 288.2 -303.2 K. The results show first order dependence on potassium ferrate(VI) and on each reductant. The observed rate constant (kobs) decreases with the increase of [OH-], the reaction was negative fraction order with respect to [OH-]. A plausible mechanism was proposed and the rate equations derived from the mechanism can explain all the experimental results. The rate constants of the rate-determining step and the thermodynamic activation parameters were calculated.

scholarly journals Thermal Decomposition Kinetics of Bis-Gem-Dinitroethyl Derivatives of N-Nitraminoacetic Acid

2020 ◽  
pp. 167-174
Author(s):  
Lyudmila А. Kruglyakova ◽  
Rudolf S. Stepanov ◽  
Konstantin V. Pekhotin ◽  
Oksana А. Golubtsova
Keyword(s):  
Thermal Decomposition ◽  
Activation Parameters ◽  
Decomposition Reaction ◽  
Decomposition Kinetics ◽  
Thermal Decomposition Kinetics ◽  
Chemical Mechanism ◽  
Initial Reaction ◽  
Mechanism Of Decomposition ◽  
Kinetics Of ◽  
Derivatives Of

Thermal decomposition kinetics of bis-gem-dinitroethyl substituted compounds based on N-nitraminoacetic acid is studied. Structural and kinetic patterns are revealed and a chemical mechanism of decomposition reaction is established, including the primary homolysis of C-NO2 bond in the gem-dinitroethyl fragment. The activation parameters are defined for the initial reaction. The reactivity of the studied compounds was analyzed and quantitative correlations between the logarithms of the rate constant, the activation energies and the steric constants of substituents in the gem-dinitroethyl group were found

scholarly journals NON-ISOTHERMAL KINETICS OF SOLID-PHASE DECOMPOSITION OF MIXTURES OF OCTOGEN WITH NITRO-NITROZOAMINES

2021 ◽  
pp. 193-198
Author(s):  
В.О. Попов ◽  
В.Н. Комов ◽  
Е.М. Попенко ◽  
А.В. Сергиенко
Keyword(s):  
Thermal Decomposition ◽  
Solid Phase ◽  
Activation Parameters ◽  
Decomposition Reaction ◽  
Isothermal Kinetics ◽  
Phase Decomposition ◽  
Formal Kinetic ◽  
Lower Activation ◽  
Kinetics Of ◽  
Derivatives Of

Определены формально-кинетические характеристики термораспада нитро-нитрозоаминов и их смесей с октогеном. Реакция разложения нитрозоаналогов октогена и нитро-нитрозопроизводных тетраазадекалина характеризуется меньшей энергией активации по сравнению с октогеном, и протекает с большей скоростью. Проведен анализ активационных параметров термораспада смесей, установлено активирующее влияние нитрозопроизводных тетраазадекалина на разложение октогена. The formal-kinetic characteristics of the thermal decomposition of nitro-nitrosoamines and their mixtures with HMX have been determined. The decomposition reaction of nitroso analogs of HMX and nitro-nitroso derivatives of tetraazadecalin is characterized by a lower activation energy compared to HMX, and proceeds at a higher rate. The analysis of the activation parameters of the thermal decomposition of the mixtures was carried out, the activating effect of the nitroso derivatives of tetraazadecalin on the decomposition of HMX was established.

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